The son of a family of devout Jehovah's Witnesses is accused of killing his teacher after being caught fleeing the scene of her murder. Meanwhile, the team is hired by the Democratic National Committee to investigate a second case in which the Chairman of the House Ethics Committee is accused of paying for sex.

When a female soldier charges a commanding officer with sexual assault, Lightman is brought to Fort Meade to find out if there's any truth to the accusation. Meanwhile, the Lightman Group is hired to determine whether the young star of a college basketball team accepted a bribe to play for the university.

The murder of a teenage girl – who is the daughter of a powerful federal judge – leads The Lightman Group to a highly competitive college-prep school where getting to the head of the class means everything. The team also investigates a NASA test pilot accused of intentionally crashing a $250 million aircraft

Lightman and Torres interrogate an imprisoned gang leader who claims to be rehabilitated. If the gang leader is freed, he might help fight inner-city violence or return to his life of crime. Foster and Loker investigate the death of a firefighter who was killed in the line of duty.

Lightman and Foster investigate the disappearance of an 11-year-old girl who may have been murdered. Meanwhile, Loker and Torres must determine whether a famous peace activist is who she claims to be and if her bestselling memoir is true, but Loker's attraction to the socially conscious woman may be clouding his assessment of her.

When Lightman is hired to find a corporate spy at a pharmaceutical company, he discovers a high-level conspiracy surrounding a new drug that could put thousands of lives at risk. The team is also hired by the State Department to assist with negotiations for the release of two Americans imprisoned in Yemen.

Lightman becomes obsessed with his investigation of two young women who committed suicide. Meanwhile, the team tries to recover billions of dollars for investors who were bilked by a Ponzi scheme.

When Assistant U.S. Attorney Zoe Landau, Lightman's ex-wife and Emily's mother, enlists Lightman to help investigate an arson case in which the only eyewitness is a 5-year-old boy, it quickly becomes clear that she and Lightman still have feelings for each other. Meanwhile, Foster and Torres question a rapper who is suspected of murder.

The Lightman Group gets embroiled in the controversial case of a policeman who shot a potentially innocent teenager. Meanwhile, investors who were bilked by a Ponzi scheme are suing The Lightman Group for botching the recovery of their money,

Eric Matheson (Garret Dillahunt) is determined to prove that he didn't murder his wife. Torres is assigned to investigate the murder, and goes to the house of the victim's sister. Matheson finds Torre's car and gets into it after she forgot to lock the door. When Torres returns, Matheson holds her at gunpoint, instructing her to drive to the Lightman Group offices. Cal makes a deal with Mattheson, asking him to let all the employees go as long as he helps prove Mattheson's innocence. Mattheson complies, and Foster, Loker, Reynolds and Torres attempt to solve the case, while Loker has second thoughts about not calling the authorities. Cal and the team find out that Mattheson was actually innocent, and that his wife was actually killed by a creditor. Mattheson demands that he sees the creditor, saying he will either take his life or Cal's. Cal pleads for Mattheson to kill him, but Foster, Loker and Reynolds trick Mattheson into letting his guard down after a disguised Loker pretends to recount the last moments of Mattheson's wife's life. As Mattheson is in a moment of rage before killing Loker, Reynolds draws his gun and shoots Mattheson, disarming him. The episode ends with Lightman at Foster's home, asking if he could sleep in her spare room for the night.